External Heating Program Changeover - Viessmann VITOTRONIC300 Installation And Service Instructions Manual

Vitotronic 300, GW2B Installation and Service

External Heating Program Changeover

Connection
Note: 'Live' contacts lead to short circuits or phase
failure. The external connection must be floating.
Plug aVD
Legend
A Floating contact
B Plug aVD of the control unit
Preselected heating program
(Contact open)
Central heating OFF/
9
DHW OFF
or
Central heating OFF/
w DHW heating ON
or Central heating ON/
w DHW heating ON
Codes
Plug aVD
Via coding address "91" in the "General" group, the
function can be assigned to the heating circuits.
Optional Connections:
H Plug aVD
H Extension EA1 (accessory, see page 127)
Extension EA1
The changeover can be achieved separately for heating
circuits 1 to 3.
Legend
A Floating contact
B Extension EA1
Code
"d5:0" in the
"Heating circuit..." group
(Factory set condition)
"d5:1" in the "Heating
circuit ..."group
Extension EA1
Set "5d", "5E" or "5F" in the "General" group to 1.
Via coding address "d8" in the "Heating circuit..."
group, the function can be assigned to the heating circuits.
Installation Sequence
Changed heating program
(Contact closed)
Constant operation with reduced room

temperature/DHW heating OFF
Constant operation with standard

room temperature, DHW heating
in accordance with coding address
"64" in the "DHW" group
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